While Cristina and Owen will have their own journey -- Kevin McKidd noted Sandra Oh's alter ego will help him find his "person" to have children with -- showrunner Shonda Rhimes tells The Hollywood Reporter that Meredith (Ellen Pompeo) will set out on a new mission this season as she adjusts to being a mother of two, including newborn Bailey.

Elsewhere, Alex (Justin Chambers) and Jo (Camilla Luddington) will bring more light-hearted moments to the medical drama as they explore their newfound relationship. Meanwhile, Callie (Sara Ramirez) and Arizona (Jessica Capshaw) will continue down the complex road ahead after the latter cheated on her wife in the season-nine finale.

The Hollywood Reporter: How will Meredith feel having taken a step back from her career when Derek begins to explore brain mapping? Could we see him go to D.C.? Shonda Rhimes: Meredith isn't going to take a step back from her career. She is going to figure out what it means to either be expected to or have people assume that she's going to take a step back or have that choice in front of her. We're going to watch Meredith have her own evolution. I call this Meredith's "lean-in" season. She's going to discover whether or not that's who she is. We're going to watch her have her own evolution, which is going to be interesting.

THR: How would you describe their journey as a couple this season?Rhimes: It's going to be complex and complicated.

THR: Will we see more of Arizona dealing with PTSD? Couples counseling?Rhimes: Possibly!

THR: How will Jackson (Jesse Williams) respond to April's (Sarah Drew) advances from the finale?Rhimes: Jackson, over the course of last season, felt like he'd been jerked around a lot. For him, this is going to be an interesting moment when he gets to answer April, and we will see that eventually. It will be an interesting moment.

THR: Will Justin Bruening return as Matthew?Rhimes: We do see Justin in more than a few episodes, yes.

THR: Alex (Justin Chambers) finally has found his person in Jo (Camilla Luddington). What sort of obstacles might they encounter?Rhimes: I have no idea at this point. I don't know that we're working toward the idea of them encountering obstacles. Right now their relationship is really new and fresh. This season is planned to be funnier than prior seasons. There's a sense of joy from them, and we're having a lot of fun with them. Even a lot of Callie's pain is going to be played in a funny way. It's going to be painful, but we're going to find the dark humor in that as opposed to just having it be either whacky or incredibly depressing.

THR: The 200th episode is something formal -- could we see a wedding? Flashbacks? Rhimes: You'll just have to watch and see!

Grey's Anatomy returns Thursday, Sept. 26 at 9 p.m. with a two-hour season premiere. Hit the comments below with what you're looking forward to seeing. Stay tuned to THR's The Live Feed for more Grey's Anatomy scoop.